The sustainable plants rating system was developed to give some guidance to plant selection in a given a given
region. The US Green Building Council LEED® program relies on the plant professionals to select the best plants
that are most sustainable and are not invasive in a given region.

The Cincinnati Zoo & Botanical Garden has taken the lead in creating this rating system based on our work
with tracking plants for over 25 years. There are many different species that we have worked with at the
CZBG and the information is invaluable. We also have taught many different plant courses over the years for
University of Cincinnati and Cincinnati State and Technical College as well as helped develop the Sustainable
Plants Class with the Horticulture program at Cincinnati State.

Arboretums around the region are another vital source of this information. We did not just base our
recommendations on the CZBG. We are working with and will continue to work with local arboretums such as
Spring Grove Cemetery and Arboretum. Spring Grove may have one of the most significant plant collections
in the United States. Between the CZBG (1875) and Spring Grove Cemetery (1845) there is a wealth of plant
knowledge to be gained. Other arboretums with incredible collections include Rowe Arboretum, Mt. Airy
Forest and Arboretum, Boone County Arboretum in Northern Kentucky, and the many parks of Cincinnati and
Hamilton County. The city of Cincinnati also has one of the strongest Urban Forestry Programs in the country.
They also have kept great records on their plantings.

Another source of information comes from our involvement with www.plantplaces.com. This website
identifies specimens locally that are currently growing in our region. It is like an online arboretum. Specimens
are identified, photographed and located to give real proof that a specimen is growing in our region. The more
plants identified of a particular species the greater confidence one has of the plant doing well in our region.
Many of the plants from the above arboretums are documented on this website.

The last source of information comes from the nursery and landscape industry that provides the plants
and installs new varieties around the region. Nurseries and the landscape community all play a vital role in
increasing the diversity in which our landscapes are made of.

Sustainable Plants Rating System - Definitions

Categories

Categories are separated out by size of the plant. The larger the tree the more ecosystem services it
will provide through shading, stormwater mitigation, carbon sequestration, and providing "green" to an
environment. We use in landscaping several size categories for trees. Here are those categories as well as the
letter signifying what category it is in:

A = Large Trees over 50' +

B = Medium Trees 25' 50'

C = Small Trees under 25'

D = Large Shrubs 8' +

E = Medium Shrubs 4' - 8'

F = Small Shrubs under 4'

G= Groundcovers and Vines

H = Bamboo

Within each of these categories are a number system that reflects our levels of confidence on these plants
performing in the landscape based on our records and observations. We also use the tools from i-Tree to help
base some of our ratings. I= Herbaceous Perennials, J = Ornamental Grasses, K = Turfgrass and L = Annuals will
be added as soon as time allows.

The scale is based on 1-5.

5 = Outstanding Best in Category, Highly Recommended

4 = Very Good Highly Recommended

3 = Good Recommended (may be site specific)

2 = Fair Caution! Not enough information available. Could be a weak performer.

1 = Poor Not Recommended for our region

Click one of the gray bars below to see sustainability ratings of plants in that category.